I guess the research is at the end
I'd say the Winner is Tom of Finland
Touko Laaksonen, best known by his pseudonym Tom of Finland (8 May 1920 – 7 November 1991) was a Finnish artist notable for his stylized homoerotic and fetish art and his influence on late twentieth century gay culture. He has been called the "most influential creator of gay pornographic images" by cultural historian Joseph W. Slade.[3]
Over the course of four decades he produced some 3500 illustrations, mostly featuring men with exaggerated primary and secondary sex traits: heavily muscled torsos, limbs, and buttocks, and large penises. Tight or partially removed clothing showed off these traits, with the penis often visible as a bulge in tight trousers or prominently displayed for the viewer. His drawings frequently feature two or more men either immediately preceding or during explicit sexual activity. Nearly all of his characters were versatile and obviously enjoyed the bottom as well as the top role in sexual intercourse.
http://en.wikipedia.org/wiki/Tom_of_Finland
